Smoking
Posted: Wed Jun 18, 2008 12:26 pmHere's an interesting one - I don't know any more about it than this, so I am not expressing any opinion on its validity.
It is a secure link which requires a password, so I have justed posted the precis content.
Smoking linked with mid-life cognitive decline 13 Jun 2008 Archives of Internal Medicine vol. 168, pp. 1165-1173.
Reference: Sabia, S. Marmot, M. et al. 2008, ‘Smoking history and cognitive function in middle age from the Whitehall II Study.’
Smoking is associated with poor memory and a loss of reasoning ability in mid-life, supporting the hypothesis that it is also linked with dementia in old age.
The Whitehall II Study recruited about 10,000 public servants in 1985-1988. By the fifth assessment in 1997-1999, when they averaged about 55 years of age, male smokers were twice as likely to have died, and female smokers were 2.5 times as likely to have died, compared to non-smokers.
Cognitive tests at the fifth assessment explored memory, reasoning, vocabulary and verbal fluency. Compared to never-smokers, current smokers were 37% more likely to be in the lowest quintile for cognitive performance. After adjusting for multiple confounders, they remained at higher risk of having poor memory.
The study also examined changes in cognitive performance between the fifth and seventh assessment, five years later. There was a decline in reasoning ability among smokers during this time.
A recent meta-analysis had concluded that smoking was a risk factor for dementia. However, examining the effect in older people was problematic because studies were necessarily based on those who had ‘survived’ smoking. Investigating changes before the onset of dementia might be more productive, potentially indicating more subtle adverse effects before smokers died of other diseases.
Analyses of smoking were complicated by the fact that smoking habits were now changing markedly throughout life. Public health messages and social pressures had had their desired effect and smoking rates were falling, leaving a substantial number of ex-smokers in the population. The Whitehall II Study found that people who were ex-smokers at baseline had a lower likelihood of cognitive impairments at later assessments, probably because they had also improved other aspects of their health including exercise levels and diet.
It is a secure link which requires a password, so I have justed posted the precis content.
Smoking linked with mid-life cognitive decline 13 Jun 2008 Archives of Internal Medicine vol. 168, pp. 1165-1173.
Reference: Sabia, S. Marmot, M. et al. 2008, ‘Smoking history and cognitive function in middle age from the Whitehall II Study.’
Smoking is associated with poor memory and a loss of reasoning ability in mid-life, supporting the hypothesis that it is also linked with dementia in old age.
The Whitehall II Study recruited about 10,000 public servants in 1985-1988. By the fifth assessment in 1997-1999, when they averaged about 55 years of age, male smokers were twice as likely to have died, and female smokers were 2.5 times as likely to have died, compared to non-smokers.
Cognitive tests at the fifth assessment explored memory, reasoning, vocabulary and verbal fluency. Compared to never-smokers, current smokers were 37% more likely to be in the lowest quintile for cognitive performance. After adjusting for multiple confounders, they remained at higher risk of having poor memory.
The study also examined changes in cognitive performance between the fifth and seventh assessment, five years later. There was a decline in reasoning ability among smokers during this time.
A recent meta-analysis had concluded that smoking was a risk factor for dementia. However, examining the effect in older people was problematic because studies were necessarily based on those who had ‘survived’ smoking. Investigating changes before the onset of dementia might be more productive, potentially indicating more subtle adverse effects before smokers died of other diseases.
Analyses of smoking were complicated by the fact that smoking habits were now changing markedly throughout life. Public health messages and social pressures had had their desired effect and smoking rates were falling, leaving a substantial number of ex-smokers in the population. The Whitehall II Study found that people who were ex-smokers at baseline had a lower likelihood of cognitive impairments at later assessments, probably because they had also improved other aspects of their health including exercise levels and diet.
